The requirements of complex sample monitoring present a growing need for a new generation of highly localized enzyme electrodes that operate in non-processed or raw samples and have multi-analyte capability. This project's objective is to establish the feasibility of novel colloidal gold/immobilized enzyme based raw sample/multi-analyte electrodes. The specific objective is to develop a biosensor that can measure high density lipoproteins in whole blood. We recently established that colloidal gold with an active enzyme immobilized on the surface can be electro-deposited onto an electrode surface in a manner that maintains the enzyme's activity. This discovery will be exploited in research leading to new and improved sensor devices. Raw sample/multi-analyte systems may be fabricated by deposition of colloidal gold with immobilized enzymes onto separate channels of a multi-channel electrode substrate. These multi- channel, spatially resolved, multi-signal enzyme electrodes can ultimately lead to a new generation of multi-analyte sensors. The researchers submitting this proposal have collaborated successfully to develop prototype electrochemical enzyme sensors in the past. PROPOSED COMMERCIAL APPLICATION: A new marketable micro-scale multi- analyte sensor based on novel enzyme immobilization methods will result in a device capable of improved rapid analytical characterization of multi- component non-processed samples.